If you've ever wanted a way to monitor your doorbell from anywhere—complete with video and audio—Instructables user macgeek shows off how to build a system that monitors your doorbell, than kicks you video on your iPhone of the person at the door so you can talk with them.

The project uses FaceTime to send video over the network, through a Mac, and then to the iPhone. You'll also need an Arduino, FaceTime compatible webcam, a USB hub, audio converter, speaker, and a microphone. It's an expensive project (about $800 for everything including the computer), but chances are you have most of it laying around already. That said, if you'd like to monitor who's hitting your doorbell when you're not home, it works. It does so over the cloud too, so if you're out of town and don't want to miss that package from UPS you can still tell them to hide it away somewhere. Head over to Instructables for the full guide.